Merge pull request #150 from erco77/master

Rewrite fluid CodeEditor syntax highlighting for issue #135

1 files changed, 60 insertions, 256 deletions

diff --git a/fluid/CodeEditor.cxx b/fluid/CodeEditor.cxx
index 4dd1cef96..3d7d47515 100644
--- a/fluid/CodeEditor.cxx
+++ b/fluid/CodeEditor.cxx
@@ -1,7 +1,8 @@
 //
 // Code editor widget for the Fast Light Tool Kit (FLTK).
+// Syntax highlighting rewritten by erco@seriss.com 09/15/20.
 //
-// Copyright 1998-2016 by Bill Spitzak and others.
+// Copyright 1998-2020 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -24,7 +25,6 @@
 #include <ctype.h>
 #include "CodeEditor.h"
 
-
 Fl_Text_Display::Style_Table_Entry CodeEditor::
                 styletable[] = {        // Style table
                   { FL_FOREGROUND_COLOR, FL_COURIER,        11 }, // A - Plain
@@ -33,83 +33,8 @@ Fl_Text_Display::Style_Table_Entry CodeEditor::
                   { FL_BLUE,             FL_COURIER,        11 }, // D - Strings
                   { FL_DARK_RED,         FL_COURIER,        11 }, // E - Directives
                   { FL_DARK_RED,         FL_COURIER_BOLD,   11 }, // F - Types
-                  { FL_BLUE,             FL_COURIER_BOLD,   11 }  // G - Keywords
-                };
-const char * const CodeEditor::
-                code_keywords[] = {     // Sorted list of C/C++ keywords...
-                  "and",
-                  "and_eq",
-                  "asm",
-                  "bitand",
-                  "bitor",
-                  "break",
-                  "case",
-                  "catch",
-                  "compl",
-                  "continue",
-                  "default",
-                  "delete",
-                  "do",
-                  "else",
-                  "false",
-                  "for",
-                  "goto",
-                  "if",
-                  "new",
-                  "not",
-                  "not_eq",
-                  "operator",
-                  "or",
-                  "or_eq",
-                  "return",
-                  "switch",
-                  "template",
-                  "this",
-                  "throw",
-                  "true",
-                  "try",
-                  "while",
-                  "xor",
-                  "xor_eq"
-                };
-const char * const CodeEditor::
-                code_types[] = {        // Sorted list of C/C++ types...
-                  "auto",
-                  "bool",
-                  "char",
-                  "class",
-                  "const",
-                  "const_cast",
-                  "double",
-                  "dynamic_cast",
-                  "enum",
-                  "explicit",
-                  "extern",
-                  "float",
-                  "friend",
-                  "inline",
-                  "int",
-                  "long",
-                  "mutable",
-                  "namespace",
-                  "private",
-                  "protected",
-                  "public",
-                  "register",
-                  "short",
-                  "signed",
-                  "sizeof",
-                  "static",
-                  "static_cast",
-                  "struct",
-                  "template",
-                  "typedef",
-                  "typename",
-                  "union",
-                  "unsigned",
-                  "virtual",
-                  "void",
-                  "volatile"
+                  { FL_BLUE,             FL_COURIER_BOLD,   11 }, // G - Keywords
+                  { 220, /* med cyan */  FL_COURIER,        11 }  // H - Single quote chars
                 };
 
 // attempt to make the fluid code editor widget honour textsize setting
@@ -123,139 +48,53 @@ void CodeEditor::textsize(Fl_Fontsize s) {
 } // textsize
 
 
-// 'compare_keywords()' - Compare two keywords...
-extern "C" {
-  static int compare_keywords(const void *a, const void *b) {
-    return strcmp(*((const char **)a), *((const char **)b));
-  }
-}
-
 // 'style_parse()' - Parse text and produce style data.
-void CodeEditor::style_parse(const char *text, char *style, int length) {
-  char          current;
-  int           col;
-  int           last;
-  char          buf[255],
-                *bufptr;
-  const char    *temp;
-
+void CodeEditor::style_parse(const char *in_tbuff,         // text buffer to parse
+                             char       *in_sbuff,         // style buffer we modify
+                             int         in_len,           // byte length to parse
+                             char        in_style) {       // starting style letter
   // Style letters:
   //
-  // A - Plain
-  // B - Line comments
-  // C - Block comments
-  // D - Strings
-  // E - Directives
-  // F - Types
-  // G - Keywords
-
-  for (current = *style, col = 0, last = 0; length > 0; length --, text ++) {
-    if (current == 'B' || current == 'F' || current == 'G') current = 'A';
-    if (current == 'A') {
-      // Check for directives, comments, strings, and keywords...
-      if (col == 0 && *text == '#') {
-        // Set style to directive
-        current = 'E';
-      } else if (strncmp(text, "//", 2) == 0) {
-        current = 'B';
-        for (; length > 0 && *text != '\n'; length --, text ++) *style++ = 'B';
-
-        if (length == 0) break;
-      } else if (strncmp(text, "/*", 2) == 0) {
-        current = 'C';
-      } else if (strncmp(text, "\\\"", 2) == 0) {
-        // Quoted quote...
-        *style++ = current;
-        *style++ = current;
-        text ++;
-        length --;
-        col += 2;
-        continue;
-      } else if (*text == '\"') {
-        current = 'D';
-      } else if (!last && (islower(*text) || *text == '_')) {
-        // Might be a keyword...
-        for (temp = text, bufptr = buf;
-             (islower(*temp) || *temp == '_') && bufptr < (buf + sizeof(buf) - 1);
-             *bufptr++ = *temp++) {
-          // nothing
-        }
-
-        if (!islower(*temp) && *temp != '_') {
-          *bufptr = '\0';
-
-          bufptr = buf;
-
-          if (bsearch(&bufptr, code_types,
-                      sizeof(code_types) / sizeof(code_types[0]),
-                      sizeof(code_types[0]), compare_keywords)) {
-            while (text < temp) {
-              *style++ = 'F';
-              text ++;
-              length --;
-              col ++;
-            }
-
-            text --;
-            length ++;
-            last = 1;
-            continue;
-          } else if (bsearch(&bufptr, code_keywords,
-                             sizeof(code_keywords) / sizeof(code_keywords[0]),
-                             sizeof(code_keywords[0]), compare_keywords)) {
-            while (text < temp) {
-              *style++ = 'G';
-              text ++;
-              length --;
-              col ++;
-            }
-
-            text --;
-            length ++;
-            last = 1;
-            continue;
-          }
-        }
-      }
-    } else if (current == 'C' && strncmp(text, "*/", 2) == 0) {
-      // Close a C comment...
-      *style++ = current;
-      *style++ = current;
-      text ++;
-      length --;
-      current = 'A';
-      col += 2;
-      continue;
-    } else if (current == 'D') {
-      // Continuing in string...
-      if (strncmp(text, "\\\"", 2) == 0) {
-        // Quoted end quote...
-        *style++ = current;
-        *style++ = current;
-        text ++;
-        length --;
-        col += 2;
-        continue;
-      } else if (*text == '\"') {
-        // End quote...
-        *style++ = current;
-        col ++;
-        current = 'A';
-        continue;
-      }
-    }
-
-    // Copy style info...
-    if (current == 'A' && (*text == '{' || *text == '}')) *style++ = 'G';
-    else *style++ = current;
-    col ++;
-
-    last = isalnum(*text) || *text == '_' || *text == '.';
-
-    if (*text == '\n') {
-      // Reset column and possibly reset the style
-      col = 0;
-      if (current == 'B' || current == 'E') current = 'A';
+  // 'A' - Plain
+  // 'B' - Line comments  // ..
+  // 'C' - Block comments /*..*/
+  // 'D' - Strings        "xxx"
+  // 'E' - Directives     #define, #include..
+  // 'F' - Types          void, char..
+  // 'G' - Keywords       if, while..
+  // 'H' - Chars          'x'
+
+  StyleParse sp;
+  sp.tbuff  = in_tbuff;
+  sp.sbuff  = in_sbuff;
+  sp.len    = in_len;
+  sp.style  = in_style;
+  sp.lwhite = 1;        // 1:while parsing over leading white and first char past, 0:past white
+  sp.col    = 0;
+  sp.last   = 0;
+
+  // Loop through the code, updating style buffer
+  char c;
+  while ( sp.len > 0 ) {
+    c = sp.tbuff[0];  // current char
+    if ( sp.style == 'C' ) {                              // Started in middle of comment block?
+      if ( !sp.parse_block_comment() ) break;
+    } else if ( strncmp(sp.tbuff, "/*", 2)==0 ) {         // C style comment block?
+      if ( !sp.parse_block_comment() ) break;
+    } else if ( c == '\\' ) {                             // Backslash escape char?
+      if ( !sp.parse_escape() ) break;
+    } else if ( strncmp(sp.tbuff, "//", 2)==0 ) {         // Line comment?
+      if ( !sp.parse_line_comment() ) break;
+    } else if ( c == '"' ) {                              // Start of double quoted string?
+      if ( !sp.parse_quoted_string('"', 'D') ) break;
+    } else if ( c == '\'' ) {                             // Start of single quoted string?
+      if ( !sp.parse_quoted_string('\'', 'H') ) break;
+    } else if ( c == '#' && sp.lwhite ) {                 // Start of '#' directive?
+      if ( !sp.parse_directive() ) break;
+    } else if ( !sp.last && (islower(c) || c == '_') ) {  // Possible C/C++ keyword?
+      if ( !sp.parse_keyword() ) break;
+    } else {                                              // All other chars?
+      if ( !sp.parse_all_else() ) break;
     }
   }
 }
@@ -267,12 +106,9 @@ void CodeEditor::style_unfinished_cb(int, void*) { }
 void CodeEditor::style_update(int pos, int nInserted, int nDeleted,
                               int /*nRestyled*/, const char * /*deletedText*/,
                               void *cbArg) {
-  CodeEditor    *editor = (CodeEditor *)cbArg;
-  int           start,                          // Start of text
-                end;                            // End of text
-  char          last,                           // Last style on line
-                *style,                         // Style data
-                *text;                          // Text data
+  CodeEditor *editor = (CodeEditor*)cbArg;
+  char       *style,                         // Style data
+             *text;                          // Text data
 
 
   // If this is just a selection change, just unselect the style buffer...
@@ -299,48 +135,16 @@ void CodeEditor::style_update(int pos, int nInserted, int nDeleted,
   // callbacks...
   editor->mStyleBuffer->select(pos, pos + nInserted - nDeleted);
 
-  // Re-parse the changed region; we do this by parsing from the
-  // beginning of the line of the changed region to the end of
-  // the line of the changed region...  Then we check the last
-  // style character and keep updating if we have a multi-line
-  // comment character...
-  start = editor->mBuffer->line_start(pos);
-  // the following code checks the style of the last character of the previous
-  // line. If it is a block comment, the previous line is interpreted as well.
-  int altStart = editor->mBuffer->prev_char(start);
-  if (altStart>0) {
-    altStart = editor->mBuffer->prev_char(altStart);
-    if (altStart>=0 && editor->mStyleBuffer->byte_at(start-2)=='C')
-      start = editor->mBuffer->line_start(altStart);
-  }
-  end   = editor->mBuffer->line_end(pos + nInserted);
-  text  = editor->mBuffer->text_range(start, end);
-  style = editor->mStyleBuffer->text_range(start, end);
-  if (start==end)
-    last = 0;
-  else
-    last  = style[end - start - 1];
-
-  style_parse(text, style, end - start);
+  // Reparse whole buffer, don't get cute. Maybe optimize range later
+  int len = editor->buffer()->length();
+  text  = editor->mBuffer->text_range(0, len);
+  style = editor->mStyleBuffer->text_range(0, len);
 
-  editor->mStyleBuffer->replace(start, end, style);
-  editor->redisplay_range(start, end);
+  style_parse(text, style, editor->mBuffer->length(), 'A');
 
-  if (start==end || last != style[end - start - 1]) {
-    // The last character on the line changed styles, so reparse the
-    // remainder of the buffer...
-    free(text);
-    free(style);
-
-    end   = editor->mBuffer->length();
-    text  = editor->mBuffer->text_range(start, end);
-    style = editor->mStyleBuffer->text_range(start, end);
-
-    style_parse(text, style, end - start);
-
-    editor->mStyleBuffer->replace(start, end, style);
-    editor->redisplay_range(start, end);
-  }
+  editor->mStyleBuffer->replace(0, len, style);
+  editor->redisplay_range(0, len);
+  editor->redraw();
 
   free(text);
   free(style);
@@ -394,7 +198,7 @@ CodeEditor::CodeEditor(int X, int Y, int W, int H, const char *L) :
                  sizeof(styletable) / sizeof(styletable[0]),
                  'A', style_unfinished_cb, this);
 
-  style_parse(text, style, mBuffer->length());
+  style_parse(text, style, mBuffer->length(), 'A');
 
   mStyleBuffer->text(style);
   delete[] style;